Summary of areas receiving potential synaptic input from the NI
| Area | Abbreviation | sypGFP | Reference |
|---|---|---|---|
| Olfactory area | |||
| Anterior olfactory n. | AO | + | Figure 10B |
| Telencephalon | |||
| Cerebral cortex | |||
| Cingulate cortex | Cg | ++ | Figure 10C,P,S |
| Claustrum | Cl | + | Figure 10F,M |
| Dorsal peduncular cortex | DP | + | Figure 10I |
| Infralimbic cortex | IL | + | |
| Orbital cortex, medial | MO | + | |
| Prelimbic cortex | Prl | + | Figure 10C |
| Retrosplenial cortex | RS | ++ | Figure 11G |
| Hippocampus | |||
| CA1 field, oriens layer | CA1 | + | Figure 11C |
| CA2 field, oriens layer | CA2 | + | Figure 11C |
| CA3 field, oriens layer | CA3 | + | |
| Dentate gyrus | DG | + | |
| Striatum/pallidum | |||
| Dorsal tenia tecta | DTT | ++ | Figure 10E |
| Nucleus diagonal band | |||
| Horizontal limb | HDB | ++ | |
| Vertical limb | VDB | +++ | Figure 10H,L |
| Septum | |||
| Lateral septal n., dorsal | LSD | + | Figure 10 I,Q |
| Lateral septal n., intermediate | LSI | ++ | Figure 10H,L,Q |
| Medial septal n. | MS | +++ | Figure 10H,I,K |
| Septofimbrial n. | SFi | + | |
| Triangular septal n. | TS | + | |
| Diencephalon | |||
| Thalamus | |||
| Zona incerta | ZI | + | Figure 11B |
| Hypothalamus | |||
| Lateral hypothalamic area | LH | +++ | Figures 10T, 11B,F |
| Posterior hypothalamic area | PH | ++ | Figure 11F |
| Preoptic area, lateral | LPO | +++ | Figure 10O |
| Supramammillary n. | SuM | + | |
| Mesencephalon | |||
| Dorsal raphe n., dorsal part | DRD | + | Figure 11R |
| Dorsal raphe n., inferior part | DRI | ++ | Figure 11P,R,S |
| Interpeduncular nucleus1 | IP | +/− | Figure 11I,K |
| Rostromedial tegmental n.2 | RMTg | +++ | Figure 11K |
| Ventral tegmental area3 | VTA | +/− | Figure 11I,K |
| Periaqueductal gray | PAG | + | Figure 11N |
| Rhombencephalon | |||
| Central gray, pontine | PnO | ++ | Figure 11M,P,S |
| Median raphe n. | MnR | + | Figure 11M,P,S |
| Nucleus incertus (cell bodies) | NI/O | +++ | Figure 7 |
| Paramedian raphe n. | PMnR | +++ | Figure 11M,P,S |
| Anterior tegmental n.4 (caudal RMTg) | ATg | ++ | Figure 11M |
The NI of Rln3Cre mice was injected with a mixture of Cre-dependent AAV-expressing sypGFP and tdT as shown in Figure 7, strategy 2. The summary is based on the case appearing in Figures 10, 11, but further supporting data were derived from the case shown in Figures 12, 13, and injected cases not shown. The density of afferents from the NI was scored from + to +++ based on the appearance of punctate sypGFP fluorescence, which is consistent with presynaptic labeling. The designation +/− is reserved for areas in which tdT-labeled fibers were observed, but little or no sypGFP, suggesting labeled fibers of passage. No consistent Rln3Cre -dependent labeling was observed in areas caudal to the pons.
↵1 Labeled fibers appear immediately adjacent to the IP, but little synaptic labeling is seen within the nucleus.
↵2 The rostromedial tegmental nucleus is not defined in standard atlases (Paxinos and Franklin, 2001) but resides just dorsolateral to the IP; this area is known to send GABAergic input to the VTA (Quina et al., 2015).
↵3 sypGFP labeling is defined within the VTA as anatomically defined, but it does not appear adjacent to DA neurons in this area.
↵4 The area defined as the anterior tegmental nucleus in standard atlases has been shown to contain neurons with similar properties to the RMTg, and has been labeled the caudal RMTg (cRMTg, Quina et al., 2015).